Optimizing the synergy between alloy and alloy–oxide interface for CO oxidation in bimetallic catalysts

Abstract

Creating synergetic metal-oxide interfaces is a promising strategy to promote the catalytic performance of heterogeneous catalysts. However, this strategy has been mainly applied to monometallic catalysts, while scarcely applied to...

Synergistic interface between metal Cu nanoparticles and CoO for highly efficient hydrogen production from ammonia borane

“…The peaks in the spectra at around 780.7 and 796.6 eV, associated with the satellite peaks at 785.5 and 802.5 eV, are characteristic features of the Co 2p 3/2 and 2p 1/2 of CoO, respectively. 18,39,40 Moreover, the binding energy of Co 2p 3/2 in Cu 0.5 –(CoO) 0.5 /TiO 2 (780.7 eV) is 0.2 eV higher than that (780.5 eV) of CoO/TiO 2 . The opposite trend in the Cu 2p 3/2 and Co 2p 3/2 binding energies is due to the transfer of electrons from CoO to Cu, indicating that the Cu–CoO heterostructure of Cu 0.5 –(CoO) 0.5 /TiO 2 exhibits strong electronic interactions and interfacial synergism.…”

Hydrogen Spillover Induced PtCo/CoOx Interfaces with Enhanced Catalytic Activity for CO Oxidation at Low Temperatures in Humid Conditions

“…After introducing 3% H 2 O, the E a of PtCo/CoO x /Al 2 O 3 catalyst was decreased to 44.8 kJ mol −1 , ≈2.4 and 1.4 times lower than those of Pt/Al 2 O 3 (109.3 kJ mol −1 ) and PtO x /Co 3 O 4 /Al 2 O 3 (61.3 kJ mol −1 ) under humid conditions, suggesting that the enhancement of intrinsic activity toward CO oxidation under humid conditions on PtCo/CoO x /Al 2 O 3 catalyst properly originated from the structure of PtCo clusters and the Pt─O─Co interfaces. [ 25 ] In addition, the T 100 of the PtCo/CoO x /Al 2 O 3 catalyst decreased sharply from 70 °C under dry conditions to RT under humid conditions, and T 100 of the Pt/Al 2 O 3 decreased slightly from 120 to 100 °C, while the PtO x /Co 3 O 4 /Al 2 O 3 catalyst was deactivated under humid conditions, with a significant increase in T 100 from 90 to 130 °C, indicating that the PtCo/CoO x /Al 2 O 3 exhibited remarkable water‐promoted catalytic performance (Figure 3c; Figure S17, Supporting Information).…”

“…After introducing 3% H 2 O, the E a of PtCo/CoO x /Al 2 O 3 catalyst was decreased to 44.8 kJ mol −1 , ≈2.4 and 1.4 times lower than those of Pt/Al 2 O 3 (109.3 kJ mol −1 ) and PtO x /Co 3 O 4 /Al 2 O 3 (61.3 kJ mol −1 ) under humid conditions, suggesting that the enhancement of intrinsic activity toward CO oxidation under humid conditions on PtCo/CoO x /Al 2 O 3 catalyst properly originated from the structure of PtCo clusters and the Pt─O─Co interfaces. [25] In addition, the T 100 of the PtCo/CoO also showed remarkable catalytic stability for CO oxidation with 100% CO conversion at 70 °C under humid conditions for >100 h without deactivation (Figure 3d). In comparison, the CO conversion on the PtCo/CoO x /Al 2 O 3 catalyst at 70 °C under dry conditions was gradually decreased from 100% to 20% after 100 h operation, suggesting that water can also greatly enhance the catalytic stability of PtCo/CoO x /Al 2 O 3 catalyst for CO oxidation.…”